US4763348A - Controlled power supply for key telephone system - Google Patents

Controlled power supply for key telephone system Download PDF

Info

Publication number
US4763348A
US4763348A US06/853,225 US85322586A US4763348A US 4763348 A US4763348 A US 4763348A US 85322586 A US85322586 A US 85322586A US 4763348 A US4763348 A US 4763348A
Authority
US
United States
Prior art keywords
key telephone
power supply
telephone set
key
specified
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US06/853,225
Other languages
English (en)
Inventor
Yoichiro Sano
Teruo Matsufuji
Akira Sato
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Iwatsu Electric Co Ltd
Original Assignee
Iwatsu Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Iwatsu Electric Co Ltd filed Critical Iwatsu Electric Co Ltd
Assigned to IWATSU ELECTRIC CO., LTD., A JOINT-STOCK COMPANY OF JAPAN reassignment IWATSU ELECTRIC CO., LTD., A JOINT-STOCK COMPANY OF JAPAN ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: MATSUFUJI, TERUO, SANO, YOICHIRO, SATO, AKIRA
Application granted granted Critical
Publication of US4763348A publication Critical patent/US4763348A/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/002—Arrangements for interconnection not involving centralised switching with subscriber controlled access to a line, i.e. key telephone systems
    • H04M9/003—Transmission of control signals from or to the key telephone set; signalling equipment at key telephone set, e.g. keyboard or display equipment
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems
    • H04M19/08—Current supply arrangements for telephone systems with current supply sources at the substations
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/002—Arrangements for interconnection not involving centralised switching with subscriber controlled access to a line, i.e. key telephone systems

Definitions

  • the present invention relates to a key telephone system, and more particularly to a power supply circuit from a key service unit to key telephone sets.
  • An object of the present invention is to provide a key telephone system which has a power switch in its power supply circuit whereby when a key telephone set is not used, its power switch is turned OFF to stop the power supply thereto and when the telephone set is used, the power switch is turned ON to start the power supply thereto.
  • a key telephone system characterized by the provision of a specified power supply means for supplying power to a specified key telephone set at all times, and a controlled power supply means capable of turning ON and OFF the power supply to controlled key telephone sets other than the specified one.
  • the controlled power supply means may be so arranged as to be automatically turned ON and OFF in accordance with a predetermined time schedule, or to be turned ON and OFF under control of the specified key telephone set, or to be turned ON upon receiving an incoming call, or to be turned OFF upon ON-hooking of the key telephone set after a talking operation with a calling party, or to be automatically turned ON and OFF in response to a specified dial signal incoming after automatically answering an incoming call, or to be capable of individually controlling the power supply to each controlled key telephone set.
  • FIGS. 1 and 2 are circuit diagrams illustrating examples of a power supply circuit used in conventional key telephone system
  • FIGS. 3 and 4 are circuit diagrams illustrating embodiments of the present invention.
  • FIGS. 5, 6, 7 and 8 flowcharts explanatory of examples of operation of the embodiments of the present invention.
  • a conventional power supply circuit for a key telephone set (disclosed in "IWATSU TECHNICAL JOURNAL", vol. 22, No. 2, Mar. 15, 1984.) has such an arrangement as shown in FIG. 1 or 2.
  • reference numeral 1 indicates a part of the circuit of a key service unit, 2 a part of the circuit of a key telephone set, 3 distribution cables, 4 a protecting fuse, 5 a power source unit (PWU), 6 in FIG. 1 a center-tapped transformer, 7 in FIG. 2 a normal transformer, 8 a two-winding transformer and 9 a power source unit PW for deriving DC power Vc from a commerical power supply AC of 100 volts.
  • PWU power source unit
  • the key service unit 1 and the key telephone set 2 have their voice lines LNv and data lines LNd interconnected via a four-wire balanced circuit using the center-tapped transformers 6.
  • the power Vc is supplied via the distribution cables 3 of the voice lines LNv to the power source unit PWU of the key telephone set 2 while being grounded via the distribution cables 3 of the data lines LNd, as indicated by G.
  • the power source unit PWU in the key telephone set 2 provides required power supplies VS 1 and VS 2 .
  • the voice lines LNv are interconnected via a balanced circuit using the normal transformers 7, and the data lines LNd are interconnected via a balanced circuit using the two-winding transformers 8.
  • the power Vc is supplied by being superimposed on the data lines LNd, and the required power supplies VS 1 and VS 2 are obtained from the power source unit PWU in the key telephone set 2.
  • the conventional power supply circuit is incapable of suspending the power supply to a specified key telephone set, and hence has a defect of wasteful power consumption.
  • FIG. 3 is a block diagram of the entire key telephone system including the power supply circuit which employs center-tapped transformers according to an embodiment of the present invention.
  • Reference character ME indicates a key service unit; AC the commercial power source; PW a power source unit for providing VC 1 and VC 2 ; CO-1, ... Co-n CO lines; KTA a specified key telephone set; KTB a key telephone set, which power supply is ON-OFF controlled; LN 1 , LN 2 , LN 3 and LN 4 cables for connecting the key service unit ME and the key telephone sets KTA and KTB; and KPW a power source unit which is employed as a controlled power supply in a key telephone set to obtain a predetermined power source voltage by the use of suitable means, such as a switching regulator.
  • suitable means such as a switching regulator.
  • the normal state in which all the key telephone sets KTA and KTB are operating will be referred to as the normal mode and the state in which only the key telephone set KTA is operating will be referred to as the sleep mode.
  • the normal mode a control circuit CPU of the key service unit ME is operating under control of a program of a read only memory ROM, while control circuits KPU of the key telephone sets KTA and KTB are each operating under control of a program of a read only memory KOM.
  • the power supply from the key service unit ME to the key telephone sets KTA and KTB takes place via a route [VC 1 of ME ⁇ T 1 ⁇ LN 1 ⁇ T 5 of KTA ⁇ KPW ⁇ T 6 ⁇ LN 2 ⁇ T 2 of ME ⁇ GND]in the key telephone set KTA and via a route [VC 2 of ME ⁇ T 3 ⁇ LN 3 ⁇ T 7 of KTA ⁇ KPW ⁇ T 8 ⁇ LN 4 ⁇ T 4 of ME ⁇ Q ⁇ GND]in the key telephone set KTB.
  • reference Q is a power switch, which is, in the normal mode, supplied with a high level H from a latch circuit LT via a resistor R and hence is in the ON state.
  • the control circuit CPU in the key service unit ME performs ON-OFF control of the power switch Q, so that the following operations can be effected.
  • the ON time and the OFF time of the power switch Q corresponding to each key telephone set KTB are stored in a random access memory RAM of the key service unit ME through operation of a keyboard KEY of the key telephone set KTA. Now, the route of information in this case will be described.
  • the control circuit KPU of the key telephone set KTA identifies time information in response to a change in the information from the keyboard KEY and transmits the time information from a transmitting-receiving circuit KXR to the key service unit ME. It is also possible, in this instance, that the information from the keyboard KEY be temporarily stored in a random access memory KAM and sent out therefrom at a time.
  • the control circuit CPU receives information from a transmitting-receiving circuit XR corresponding to the key telephone set KTA and stores it in a random access memory RAM.
  • the control circuit CPU compares time information of a clock circuit CLK with the OFF time read out of the random access memory RAM and, in the case of coincidence therebetween, sets a low level L in the latch circuit LT.
  • the power switch Q in turned OFF, and the power supply to the key telephonse set KTB is stopped.
  • the control circuit CPU sets a high level H in the latch circuit LT to turn ON the power switch Q, initiating the power supply to the key telephone set KTB.
  • FIG. 5 The flow of this processing is depicted in FIG. 5, including the following steps:
  • the power switches Q of all the key telephone sets KTB are turned OFF by operating the keyboard KEY of the key telephone set KTA, providing the sleep mode. After a predetermined elapsed time, the power switches Q of all the key telephone sets KTB are turned ON by operating the keyboard KEY of the key telephone set KTA, turning the sleep mode to the normal mode. The route of information in this case will be described.
  • the control circuit KPU of the key telephone set KTA identifies the OFF information of the power switch Q in response to a change in the information from the keyboard KEY and transmits the OFF information via the transmitting-receiving circuit KXR to the key service unit ME.
  • the control circuit CPU receives the OFF information via the transmitting-receiving circuit XR corresponding to the key telephone set KTA and then sets the low level L in the latch circuit LT. Thus, the power switches Q are turned OFF, stopping the power supply to the key telephone sets KTB.
  • control circuit CPU receives, from the transmitting-receiving circuit XR corresponding to the key telephone set KTA, the ON information delivered via the same route as in the above and then sets the high level H in the latch circuit LT.
  • the power switch Q is turned ON, starting the power supply to the key telephonse set KTB.
  • FIG. 6 The flow of this processing is shown in FIG. 6, including the following steps:
  • the power switch Q Upon occurrence of an incoming call to the key service unit ME in the sleep mode, the power switch Q is turned ON, providing the normal mode.
  • the key telephone set KTA or KTB answers the incoming call and upon ON-hooking after communication, the power switch Q is turned OFF, and the key telephone set KTB returns to the sleep mode.
  • the control circuit CPU receives incoming call information from an incoming call detector INC 1 of a CO line circuit COT 1 and sets the high level H in the latch circuit LT. By this operation, the power switch Q is turned ON, initiating the power supply to the key telephone set KTB.
  • the control circuit KPU Upon ON-hooking of the called key telephone set KTA of KTB, its control circuit KPU identifies ON-hooking information in response to a change in the information from the keyboard ME and sends it from the transmitting-receiving circuit KXR and the key service unit ME.
  • the control circuit CPU receives the ON-hooking information via the transmitting-receiving circuit XR corresponding to the called key telephone set KTA or KTB, and then sets the lower level L in the latch circuit LT. By this operation, the power switch Q is turned OFF, stopping the power supply to the key telephone set KTB.
  • FIG. 7 The flow of this processing is shown in FIG. 7, including the following steps:
  • the CO line circuit COT i automatically answers by a predetermined function and then connects the CO line CO-1 to a PB signal receiver PBR.
  • a predetermined function for example, in a case where the subscriber wants to hear at a remote place a message recorded during his absence, upon receiving of a specified dial signal (a voice frequency signal, for example) known by only the subscriber, the PB signal receiver PBR identifies the specified dial signal, by which the power switch Q is turned OFF, turning it in the sleep mode.
  • the sleep mode services by this special function can be received by the subscriber. After a predetermined elapsed time, the subscriber performs the same dialing operation as that for calling, thereby turning ON the power switch Q to return to the normal mode.
  • the control circuit CPU of the key service unit ME receives incoming call information from the incoming call detector INC 1 of the CO line circuit COT 1 , the control circuit CPU causes the CO line circuit COT 1 to establish a loop including the CO line and, futher, controls a speech network control circuit SWC and a speech network SW to connect the CO line circuit COT 1 to the PB signal receiver PBR.
  • the PB signal receiver PBR Upon receiving specified dial information from the subscriber, the PB signal receiver PBR transmits OFF information to the control circuit CPU, which sets the low level L in the latch circuit LT. In consequence, the power switch Q is turned OFF, stopping the power supply to the key telephone set KTB.
  • control circuit CPU receives ON information from the PB signal receiver PBR via the same route as in the above and sets the high level H in the latch circuit LT.
  • the power switch Q is turned ON, starting the power supply to the key telephone sets KTB.
  • FIG. 8 The flow of this processing is depicted in FIG. 8, including the following steps:
  • FIG. 4 illustrates the principal part of another embodiment of the power supply circuit of the present invention which employs two-winding transformers. This embodiment is identical with the embodiment of FIG. 3 in the operation signals used, the control methods and the omitted parts.
  • the control circuit CPU sets the high level H in the latch circuit LT, the power switch Q is turned ON to start the power supply to the key telephone set KTB, and when the low level L is set in the latch circuit LT, the power switch Q is turned OFF, stopping the power supply to the key telephone set KTB.
  • FIGS. 3 and 4 each illustrate a start system in which one key telephone set is connected to one power supply circuit
  • the present invention is also applicable to a branch system in which two or more key telephone sets are connected to one power supply circuit.
  • the speech network SW can be used either with a space division system or with a time division system.
  • the power supply to key telephone sets which are not used is stopped by turning ON and OFF the power switch, thereby reducing the power consumption of the key telephone system.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
US06/853,225 1985-04-30 1986-04-17 Controlled power supply for key telephone system Expired - Fee Related US4763348A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP60-93089 1985-04-30
JP60093089A JPH0738735B2 (ja) 1985-04-30 1985-04-30 ボタン電話装置

Publications (1)

Publication Number Publication Date
US4763348A true US4763348A (en) 1988-08-09

Family

ID=14072794

Family Applications (1)

Application Number Title Priority Date Filing Date
US06/853,225 Expired - Fee Related US4763348A (en) 1985-04-30 1986-04-17 Controlled power supply for key telephone system

Country Status (6)

Country Link
US (1) US4763348A (zh)
JP (1) JPH0738735B2 (zh)
CN (1) CN1009896B (zh)
DE (1) DE3613602A1 (zh)
FR (1) FR2581278A1 (zh)
GB (1) GB2174866B (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4942604A (en) * 1986-09-29 1990-07-17 Digital Telecommunications Systems, Inc. Line power control circuit for pay station telephone
US4995110A (en) * 1989-09-15 1991-02-19 Mars Incorporated Method and apparatus for keyboard adaptation to a low power controller in a coin operated telephone

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0316789U (zh) * 1989-06-29 1991-02-19
JPH0495497A (ja) * 1990-08-10 1992-03-27 Matsushita Electric Ind Co Ltd ボタン電話装置
DE4142007A1 (de) * 1991-12-19 1993-06-24 Industronic Ind Elect Gmbh Einrichtung zur uebertragung von daten- und sprachsignalen zwischen einer von mehreren sprechstellen und einer zentralen vermittlungseinrichtung
DE4233682A1 (de) * 1992-10-02 1994-04-07 Deutsche Telephonwerk Kabel Schaltungsanordnung für die Speisung von digitalen Einrichtungen
JP5342423B2 (ja) * 2009-12-10 2013-11-13 日本電信電話株式会社 ボタン電話システム

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5639673A (en) * 1979-09-07 1981-04-15 Nec Corp Electric talking current supply circuit
JPS58159055A (ja) * 1982-03-17 1983-09-21 Fujitsu Ltd 加入者回路の電源供給方式
JPS5951648A (ja) * 1982-09-17 1984-03-26 Matsushita Electric Ind Co Ltd ボタン電話装置
US4653088A (en) * 1985-03-25 1987-03-24 Wang Laboratories, Inc. Telephone circuitry with power backup

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57107664A (en) * 1980-12-25 1982-07-05 Nitsuko Ltd Electronic button telephone set
US4539437A (en) * 1982-11-30 1985-09-03 At&T Bell Laboratories Stored program power control system for improving energy efficiency for telephone sets connected into a local telephone communications system
JPS59143491A (ja) * 1983-02-04 1984-08-17 Nec Corp ボタン電話装置
JPS603296A (ja) * 1983-06-20 1985-01-09 Matsushita Electric Ind Co Ltd 電子式ボタン電話装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5639673A (en) * 1979-09-07 1981-04-15 Nec Corp Electric talking current supply circuit
JPS58159055A (ja) * 1982-03-17 1983-09-21 Fujitsu Ltd 加入者回路の電源供給方式
JPS5951648A (ja) * 1982-09-17 1984-03-26 Matsushita Electric Ind Co Ltd ボタン電話装置
US4653088A (en) * 1985-03-25 1987-03-24 Wang Laboratories, Inc. Telephone circuitry with power backup

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4942604A (en) * 1986-09-29 1990-07-17 Digital Telecommunications Systems, Inc. Line power control circuit for pay station telephone
US4995110A (en) * 1989-09-15 1991-02-19 Mars Incorporated Method and apparatus for keyboard adaptation to a low power controller in a coin operated telephone
WO1991004626A1 (en) * 1989-09-15 1991-04-04 Mars Incorporated Keyboard adaptation to low power controller in a coin telephone

Also Published As

Publication number Publication date
CN1009896B (zh) 1990-10-03
CN86102953A (zh) 1986-10-29
GB8610359D0 (en) 1986-06-04
FR2581278A1 (fr) 1986-10-31
GB2174866A (en) 1986-11-12
DE3613602A1 (de) 1986-10-30
FR2581278B1 (zh) 1994-04-22
GB2174866B (en) 1989-07-05
DE3613602C2 (zh) 1992-03-12
JPS61252794A (ja) 1986-11-10
JPH0738735B2 (ja) 1995-04-26

Similar Documents

Publication Publication Date Title
US5502762A (en) System and method for simultaneously controlling ringing at local and remote telephones
US5333190A (en) Telephone ring detection method and apparatus
US5146489A (en) Dedicated line eliminator for facsimile/telephone systems
US4763348A (en) Controlled power supply for key telephone system
US3510584A (en) Telephone system with added main line subscriber facilities
US4572928A (en) Key telephone system
US4677661A (en) Microprocessor controlled telephone unit
US4754476A (en) Premises page/intercom system utilizing telephone set component
US5070523A (en) Private automatic business exchange
US3624300A (en) Central office terminal unit for telephone carrier system
US4674118A (en) Telephone line hold and hold release apparatus
US4418244A (en) Bistable switch remotely operable over telephone line
US4511767A (en) Key telephone system signalling and control arrangement
KR910000352B1 (ko) 비상전화 시스템의 자동이득 조정방법
JPH07250360A (ja) ボタン電話装置
JPH0445036B2 (zh)
US4638123A (en) Circuit arrangement for a small PABX with a switching matrix that has electronic crosspoints
KR910002633B1 (ko) 정전 대피 통화기능을 갖는 시스템형 전화기
KR860002227Y1 (ko) 홈 키폰(Home Keyphone)의 대기음악 송출회로
KR840002134B1 (ko) 자동식 전화기 증설장치
AU618852B2 (en) Digital telephone set having an emergency switching function and communication system having the same
JPH0258497A (ja) 通信システム
JP2000083116A (ja) 加入者回線給電システム
JPS6134719B2 (zh)
JPH0245389B2 (zh)

Legal Events

Date Code Title Description
AS Assignment

Owner name: IWATSU ELECTRIC CO., LTD., 7-41-1, 1-CHOME, KUGAYA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:SANO, YOICHIRO;MATSUFUJI, TERUO;SATO, AKIRA;REEL/FRAME:004540/0686

Effective date: 19860407

FPAY Fee payment

Year of fee payment: 4

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
FP Lapsed due to failure to pay maintenance fee

Effective date: 19960814

STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362